Field of the Invention
The present invention generally relates to computer systems and artificial intelligence, and more particularly to a method of improving human-like behavior of an artificial intelligence entity in a video game.
Description of the Related Art
Video games have become a multi-billion dollar industry and are quickly moving to the forefront of interactive entertainment. Video games (also referred to as electronic gaming) can be played on a wide range of platforms with various operating systems, primarily computers (desktop. laptop, or tablet) and consoles (e.g., attached to televisions), but also mobile devices such as cellphones. Video games can be designed for solo play or for multiplayer interaction. In the latter case, human players can play against each other, or can form a team to play against “the computer”, i.e., a non-human character or other entity whose actions are controlled by the underlying computing device. A game can also have multiple human teams in competition with each other while additionally having computer-generated foes.
There are several different categories of video games that have become popular, including first-person shooter games, real-time strategy games, and role-playing games. First-person shooter games, as the name suggests, generally provide a visual image designed to mimic what a person would directly see within the virtual reality of the game, as that player's presence in the game (i.e., avatar) moves and interacts with the game environment. These games typically focus on the use of hand-held weapons or other equipment, e.g., a player equips a pistol via the game interface and then uses clicks of a mouse or other graphical pointing device to fire the pistol while aiming at various targets on the display screen. One example of a popular first-person shooter game is “Call of Duty”. Real-time strategy games allow a single player to control multiple characters, e.g., military units such as marines, tanks, and jets, to form an army. These games typically use a third-person or camera view, i.e., an overhead perspective, allowing the player to view a wide expanse of a battlefield. One example of a popular real-time strategy game is “StarCraft”. Role-playing games, as the name again suggests, generally involve a genre such as sword/sorcery or sci-fi which allows the player to assume a particular role, e.g., a wizard or a Jedi knight. Some of these games can accommodate hundreds or thousands of players within the same game environment, and are known as massively-multiplayer online role-playing games (MMORPGs). One example of a popular MMORPG is “EverQuest.”
Many of these games have sophisticated techniques to provide artificial intelligence (AI) to the computer-generated characters/units. As seen in FIG. 1, a typical game experience 10 includes a game environment 12, one or more human players 14, and one or more AI players 16. Game environment 12 can be relatively simple, or very complex. The primary game environment parameter is the particular map or maps provided, i.e., a physical setting. Players might be able to travel between multiple areas or zones each having a different map. Maps can have a variety of features such as terrain, locations (regions/waypoints), fog of war, neutral units (critters), interactive items (equipment or powerups), resources, buildings, etc. Triggers can be programmed for the specific map, i.e., when a particular condition occurs then the computer can create certain circumstances or initiate certain actions including AI player actions. Different game types may be available, such as free-for-all, capture-the-flag, deathmatch, high score, control area, etc. Games often have difficulty settings as well, such as easy, normal, hard, or very hard (insane). Other parameters not shown in FIG. 1 can also be provided, such as game speed.
A human player (player character) 14 can engage the game environment in various manners dictated by the hardware and software interfaces. For computer games, human player can use a mouse (graphical pointing device) and keyboard; for console games, a custom controller is usually provided with a joystick and multiple function keys; for cellphone games, the touch screen provides the interface. The human player may possess certain attributes, such as race or class, proficiencies and skills, equipped items and items which can be used without equipping. The human player also brings unique behaviors to the game in the form of styles, strategies, and tactics. Many gamers utilize voice communications to discuss these matters, particularly in match or tournament play. The voice communications can be provided within the game, i.e., as part of the game programming, or can be provided by third party vendors such as Ventrilo or TeamSpeak.
An AI player (non-player character) 16 is controlled via preprogrammed scripts or macros, which are basically different sets of commands that the AI player can follow. Conventional AI is mostly reactionary. An AI player can recognize and attack enemy players, gather resources, manipulate objects such as opening a door or defusing a bomb planted by an enemy, and move around the map such as by using designated waypoints to check for the presence of enemies. AI players can communicate only in a very limited form, using in-game pre-recorded chat such as radio commands.
When a game is over, win or lose, statistics may be provided to the players. The statistics may for example include the number of kills for a player (or team), number of deaths, accuracy, number of goals achieved, number of technologies acquired, number of buildings razed, etc. Some games also allow the player to save the game in the form of a replay file 18. Replay file 18 reflects general player behavior such as movement and equipment usage but does not contain any specific strategies, etc.